1. Field of the Invention
The present invention relates to cleaning apparatus and methods for removing residual toner and other particles from an image-bearing surface of an electrostatographic reproduction machine such as a copier or printer. More particularly, the present invention relates to such an apparatus and method that is suitable for cleaning and renewing such an image-bearing surface.
2. Description Relative to the Prior Art
Electrostatographic process reproduction machines such as copiers and printers for producing copies of an original document are well known. Such copies typically are produced on suitable receivers through a repeatable process that normally includes the steps of (1) using electrostatic charges in some manner to form a latent image on the surface of an image-bearing member; (2) developing the latent image with developer material that includes toner particles; (3) transferring the developed image to a suitable receiver for subsequent fusing; and (4) cleaning the image-bearing surface thereafter by removing residual toner and other particles therefrom in preparation for repeating the process steps.
The quality of the copies obtained by repeating these steps depends significantly on the effectiveness of the cleaning device or apparatus that is employed for cleaning and preparing the image-bearing surface for such reuse. Such cleaning and preparation should involve not only removing the residual toner and other particles left on the image-bearing surface after the image transfer step, but also renewing such surface by removing therefrom chemical and/or physical contamination such as scum. Conventional cleaning apparatus for removing the particles and attempting to also remove the chemical contamination include, for example, sponge roller and blade cleaners as disclosed for example in U.S. Pat. No. 4,395,113, issued Jul. 26, 1983 in the name of Buchan et al, and blade and scrubber pad cleaners as disclosed for example in U.S. Pat. No. 3,947,108, issued Mar. 30, 1976 in the name of Thettu et al. ln the '108 patent the need for renewing the surface is recognized, and means for doing so are disclosed including scrubbing or abrading the surface of the image-bearing member with a scrubbing pad in order to remove film-like contamination therefrom. The means or apparatus disclosed includes a single cleaning element such as a blade, and a single abrasive element such as a pad or roller consisting of fibers made preferably from cotton or from other fabrics such as felt or polyurethane. Importantly, it is recognized in the ' 108 patent that such an apparatus may fail to remove the film-like contamination if not mechanically biased precisely against the image-bearing surface, or if overbiased it may undesirably abrade such surface excessively. Given the particular scrubbing materials and method disclosed in the '108 patent, the apparatus disclosed therein is therefore likely to suffer from loading imprecision as the surface becomes abraded or worn out in the process. Additionally, the surface is also likely to suffer from surface scratches or abrasive marks, both of which can result from abrading the surface, and are likely to cause defects in the images produced on such surface.